Lamp holder assembly

ABSTRACT

A lamp holder assembly includes a frame structure having an interior cavity within which to mount a lamp device including electric contact blades for positioning said lamp device within said cavity and providing electrical contact thereto, and further including a plurality of stepped motor surfaces of different diametrical dimension, each of said inner surfaces being slotted to matingly receive a correspondingly diametrically sized front end display cap. A plug member is removed from a base portion of the frame structure for inserting the pair of contact blades and thereafter the plug member is ultrasonically welded within the base portion to provide an integral one-piece structure for the frame structure. The frame structure is made of a dielectric material in order to obviate previously experienced electrical shorts to a conductive frame structure.

United States Patent [1 1 Costanzo et al.

[ Dec. 4, 1973 LAMP HOLDER ASSEMBLY [75] Inventors: James J. Costanzo, River Grove;

Eugene R. Hrdlicka, Elmwood Park, both of 111.

[73] Assignee: GTE Automatic Electric Laboratories Incorporated,

Northlake, Ill.

[22] Filed: Sept. 29, 1972 [211 Appl. No.: 293,636

[52] US. Cl. 240/52 R, 240/152, 350/252,

339/176 L [51] Int. Cl. F2lv 21/00 [58] Field of Search 240/2 R, 2.1, 8.16,

240/52 R, 151, 152; 339/176 L, 208, 210 R, 218 R; 248/27; 350/252 [56] References Cited UNITED STATES PATENTS 2,946,994 7/1960 Durnke et al 339/176 L X 3,489,891 1/1970 Altissimo 240/8.l6 X

Primary ExaminerFred L. Braun Att0meyl(. Mullerheim et al.

[57] ABSTRACT A lamp holder assembly includes a frame structure having an interior cavity within which to mount a lamp device including electric contact blades for positioning said lamp device within said cavity and providing electrical contact thereto, and further including a plurality of stepped motor surfaces of different diametrical dimension, each of said inner surfaces being slotted to matingly receive a correspondingly diametrically sized front end display cap. A plug member is removed from a base portion of the frame structure for inserting the pair of contact blades and thereafter the plug member is ultrasonically welded within the base portion to provide an integral one-piece structure for the frame structure. The frame structure is made of a dielectric material in order to obviate previously experienced electrical shorts to a conductive frame structure.

1 Claim, 4 Drawing figures mmmm 41913 53 85 850 58 F IG. 4

LAMP HOLDER ASSEMBLY BACKGROUND OF THE INVENTION This invention relates generally to lamp holder assemblies commonly referred to as lamp jacks, and more particularly, relates to an improved and simplified structure for such lamp jacks.

Lamp jacks are popularly utilized as display devices in telephone communications systems as well as in other arts, and their individual structures are usually a direct result of the size and shape of the lamp bulbs to be mounted and the thicknesses of the display panels to which the lamp jacks are to be attached. One popular telephone lamp jack which is intended to be replaced by the present invention comprises arather elongated frame structure defining a central opening within which to position a generally slender cylindrical lamp bulb. A forward or front end portion of the frame structure is configured to be tubular and includes an exterior threaded portion on the extreme end thereof whereby the frame structure can be mounted to a display panel through being captured within a suitable opening in the panel by engaging threaded means. A cap structure is commonly inserted into the openended tubular end portion, the visible portion of the cap structure being usually at least translucent for permitting the observance of a lighted condition and a non-lighted condition in accordance with the display signalling function of telephone lamp jacks.

A rear end portion of the frame structure includes electrical contact means and lamp positioning means attached thereto in a related assembly of parts, the contact means comprising oppositely disposed and spaced contact fingers common end portions of which are to be disposed interiorly to the central opening for engaging conductive portions of the lamp 'bulb. The lamp positioning means also comprises oppositely disposed and spaced contact fingers common end portions of which are to be disposed interiorly to the central opening of the frame structure for positioning the lamp bulb within the central opening'The contact fingers of the electrical contact means comprise a smaller inner pair of contact fingers and the contact fingersof the lamp positioning means compriSe'a larger outer pair of contact fingers, the inner and outer pairs of contact fingers being electrically isolated from each otherand from the frame structure where the same are attached to the frame structure by interleaved layers of dielectric material.

Some features of the above-described lamp jack which are in need of improvement relate firstly to the forward end portion of the frame structure and the insertable cap structure and secondly relate to the rear end portion of the frame structure and the attached electrical contact means and lamp positioning means. It is common practice to mount the lamp jacks from the rear of a display panel and to provide an enlarged shoulder portion disposed rearwardly of the tubular end portion for limiting by means of engagement of the shoulder portion with the rear surface of the display panel, the extent of insertion of the threaded end portion through the associated panel opening. In this manner, different thicknesses of display panels can be accommodated by adjusting the linear extent of the rearward offset of the shoulder portion. The common result is that several configurations of tubular end portions are provided with different degrees of offsets for the shoulder portion. Another design feature of the front end portion of the frame structure requires that the inside diametrical dimension be varied to accommodate the appropriate diametrical size of a force fitted insertable cap structure. While the more commonly used lamp jacks and their associated cap structures are generally provided in standard sizes across the telephone industry, it has been observed that for a given standard size, the diametrical dimensions of some of the cap structures may vary in the order of mils of thickness to an extent that the integrity of the force fit of the cap structure is impaired. Accordingly, in addition to providing the capability for accommodating a variety of panel thicknesses, a number of cap sizes must also be accommodated. Also, the integrity of the force fit connection between matched size cap structures and front end portions tends to deteriorate after the cap structure has been removed several times for the purpose of front end replacement of the lamp bulb.

The frame structure has been heretofore constructed of a metal or metal-like material primarily through considerations of strength of materials and it has been found that the machine milling in order to provide for the several configurations of the front end portion is relatively expensive and that on occasion electrical short circuits occur between the conductive areas of the lamp bulb and the frame structure. It would seem that a relatively rigid frame structure could be fashioned as by molding from suitable dielectric materials such as glass filled thermoplastics whereby the possibility of an electrical short circuit through the frame structure to the display panel would be eliminated. The assembly of parts of the electrical contact means and the lamp positioning means with the requisite interleaved layers of insulation comprises an expense in terms of both the costs of initial assembly and maintenance. Additionally, the stated assembly of parts has been heretofore attached to the rear end portion of the frame structure through the use of suitable fastening devices such as rivets or screws, and it is economically desirable that the need for such separate fastening devices be eliminated as well as to eliminate the need for separate lamp positioning means apart from the frame structure and the electrical contact means.

- SUMMARY,

It is therefore among the objects of the present invention to provide for an improved structure for a lamp holder assembly wherein there is presented a single configuration for the front end portion of the frame structure which is useful for mounting with a variety of display panel thicknesses; to provide for an improved engagement between the insertable cap structure and the front end portion offthe lamp jack; to provide for the construction of the frame structure from a suitable dielectric material; and to provide for the simplification and more economical cost of the lamp jack through the elimination of the need for separate lamp positioning means, separate layers of insulating material and separate fastening devices.

In apreferred practice of the invention, an improved lamp holder assembly is fashioned comprising a generally elongated body of dielectric material having a frame structure defining an interior cavity convenient for housing therein a variety of illuminating lamp devices. The frame structure includes a forward end portion configured to be generally tubular into which an insertable cap structure is received and a rearward or base portion for mounting thereto the electrical contact means adapted for use with a selected lamp bulb. The tubular forward end portion of the frame structure includes a plurality of internal surface areas of different inside diameters and further includes slots in selected ones of said internal surface areas which extend circumferentially of the surface areas, the slots being useful to retain the cap structure within the forward end portion. Further, the forward end portion is provided with a rearwardly disposed exterior shoulder portion for limiting the extent of the front protrusion of the forward end portion through the display panel. For display panels of reduced thicknesses, different size tubular spacers can be telescopically received over the forward end portion and engaged between the shoulder portion and the rear surface of the display panel in order to provide for the proper amount of front protrusion. The rearward or base portion of the frame structure includes a removable plug member which exposes a recessed surface area in said base portion when removed. The recessed surface area and the plug member contain longitudinal slots therein which slots are complementarily aligned with said plug member in place and which slots receive therein contact means for electrically engaging the illuminating lamp device. The frame structure includes at least one circumferential rib member disposed intermediately of said interior cavity for positioning the lamp device and strengthening the frame structure.

THE DRAWING FIG. 1 is an exploded perspective view of a prior art lamp holder assembly showing separate electrical contact means and lamp positioning means to be mounted to a base portion of a frame structure for said assembly;

FIG 2 is an exploded perspective view of a lamp holder assembly in accordance with the present invention and showing a plug member removed from a base portion thereof;

FIG. 3 is an end plan view of the lamp holder assembly of FIG. 2 showing the manner in which the plug member and the base portion 'cooperate to mount a pair of contact blades; and

FIG. 4 is a side elevational view of the assembled lamp holderassembly of FIG. 2.

DETAILED DESCRIPTION Now referring to FIG. 1, there is shown a popular prior art type telephone lamp holder assembly or lamp jack including a relatively elongated frame structure 21 having a tubular forward or front end portion 22 and a rearward or base portion 23 interconnected by two parallel spaced side members 24. The side members 24 define together with the front end portion 22 and the base portion 23 an interior intermediate cavity. 27 within which there may be positioned a generally slender cylindrical lamp device or bulb 29. The front end portion 22 of the frame structure 21 is configured to be generally tubular to permit the front mounting of the lamp bulb 29 as by means of some suitable extracting tool. The extreme end portion of the front end portion 22 contains a set of exterior threads 31 for use in mounting the lamp jack 20 to a display panel (not shown) through the portion 22 being captured within a suitable opening in the panel by engaging threaded means. A cap structure 32 is commonly inserted into the open-ended tubular end portion 22 and has a rim area 34 employed to enhance a force fit engagement therebetween. A visible end portion 33 of the cap structure 32 is made at least translucent for permitting the observance of a lighted condition and a non-lighted condition in accordance with the display signalling function of telephone lamp jacks.

Separate fastening devices such as a pair of screws 35 are used to mount an assembly of parts 40 to the base portion 23 of the frame structure 21. The assembly of parts 40 is generally captured between two outer bracing plates 37, the lower one of which includes threaded openings therein for engaging the threaded screws 35. The assembly of parts 40 includes electrical contact means in the form of a pair of oppositely disposed and spaced-apart contact finger-like blades 41, and further includes lamp positioning means in the form of another pair of oppositely disposed and spaced-apart contact finger-like blades 43. Base portions of the electrical contact blades 41 and the lamp positioning contact blades 43 are electrically isolated from each other, from the base portion 23 of the frame structure 21 and from the plates 37 by means of a plurality of insulating pads 45. In the particular orientation of the assembly of parts 40 as shown in FIG. 1, the electrical contact blades 41 comprise an inner pair of blades and the lamp positioning contact blades 43 comprise an outer pair of blades. The interior common end portions of the electrical contact blades 41 are effective to grasp opposite sides of the lamp bulb 29 with the contact blades 41 conductively engaging metal electrode plates 46 provided on the lamp bulb 29. The interior common end portions of the lamp positioning blades 43 are effective to grasp the circumferential dimension of the lamp bulb 29 for positioning the bulb 29 within the cavity 27. It is convenient for the contact blades 43 to engage the lamp bulb 29 at any portion of its length dimension including along the electrode plates 46 since the pairs of contact blades 41 and 43 are insulated from each other. A threaded ring member 47 is used to illustrate an embodiment of the engaging threaded means used to mount the frame structure 21 to the associated display panel-A shoulder or ledge portion .49 is accordingly provided rearwardly of the forward end portion 22 whereby the thickness of the display panel is captured between the ring member 47 and the shoulder portion 49.

Now in accordance with the present invention, an improved lamp holder assembly or lamp jack 50 is shown in FIG. 2 in the form of a generally elongated frame structure 51. The frame structure 51 includes a tubular forward or front end portion 52, a rearward or base portion 53 and a pair of parallel spaced side members 54 defining therebetween an interior intermediate cavity 57 within which to mount the same or a similar lamp bulb as the lamp bulb 29. Again, the lamp bulb 29 is intended to be inserted into and removed from the frame structure 51 through the open-ended configuration of the front end portion 52 of the frame structure 51. A pair of annular rib members 58 and 59 are anchored to the side members 54 and are disposed in space relation to each other along the-length dimension of the cavity 57, such rib members functioning as strengthening means for the frame structure 21 and positioning means for the lamp bulb 29.

In its preferred embodiment, the front end portion 52 of the frame structure 51 includes a set of exterior threads 61 useful for mounting the lamp jack 50 onto a suitable display panel and a rearwardly offset shoulder or ledge portion 63 like the shoulder portion 49 for providing a limit to the insertion of the threads 61 through a selected opening in the display panel. When the thickness of the display panel is reduced from the maximum amount of thickness permitted to be accommodated by the rearward offset of the shoulder-portion 63, an annular spacer member 64 to be telescopically received over the threads 61 can be utilized to provide a proper fit. Obviously, the spacer member 64 will have a length dimension appropriate to the adjustment needed for the different display panel thicknesses. A separate cap structure 65 is to be insertedly mounted on the open-end of the front end portion 52. The cap structure 65 is preferably formed as an integrally molded plastic-like member having generally translucent characteristics. The cap structure 65 includes a visible enlarged diametrical portion 65a and a reduced diametrical portion 65b depending therefrom, the latter portion being intended to be inserted into the tubular front end portion 52. In order to provide for an improved mounting technique of the cap structure over the force fit mounting technique shown in FIG. l, the front end portion 52 is provided with stepped inner surfaces 67 and 69 presenting two different inner diameters for improved matching of different size cap structures 65. The inner surfaces 67 and 69 include opposite circumferential slots 71 and 73, respectively, which accept the insertion of a ridge portion 65c provided on the reduced diametrical portion 65b of an appropriate size cap structure 65. As is done forthe prior art cap structure 33, the reduced diametrical portion 65b of the cap structure 65 is provided with a plurality of lengthwise slots 65d evenly spaced about the circumference of the reduced portion 65b for defining a plurality of flexible tines.

The base portion 53 of the frame structure 51 includes a removable plate-like plug member 80 which exposes when removed from the base portion53, a recessed surface area81 disposed between a pair of side walls 83. The recessed surface area 81 includes a pair of longitudinally extending slots 84'of suitable width and depth to permit the edgewise insertion of a pair of flat-like elongated contact blades 85. The plug member 80 also includes a pair of spaced slots '86 which are complementarily aligned with the slots 84 to receive edge portions of the contact blades 85 with the plug member appropriately matched with its receiving base portion 53. The contact blades 85 include indexing notches 88 along their edge portions which match during mounting with raised portions 89 within the slots 84 and 86 for the purpose of locating the contact blades 85 longitudinally with respect to the base portion 53. The contact blades 85 have interior common end portions 85a configured to present indexing offsets to be received within suitable channel portions of the lamp bulb 29 to provide for a snap-in mounting of the bulb 29 with respect to the contact blades 85 as is shown most clearly in FIG. 4. Exterior common end portions 85b of the contact blades 85 are shown to have a configuration to facilitate a soldered connection, but it should be understood that the end portions 85b could be provided with a wrapped terminal configuration instead. Further, the plug member 80 includes an indexing post 91 disposed generally centrally thereof and the base portion includes an indexing notch or opening 93 disposed in the recessed surface 81 for reception of the indexing post 91 when the plug member is matched with its receiving base portion 53 as is clearly shown in FIG. 3.

In accordance with the object of the invention to provide a more economical frame structure for the lamp jack 50, the frame structure 51 is configured from a suitable glass filled thermoplastic material such as polycarbonate or polysulfone. The frame structure 51 comprises an integrally molded plastic-like one-piece structure providing adequate ventiliation for the lamp bulb 29 through the openings into the cavity 57 lying between the ribs 58 and 59. The lamp bulb 29 is firmly held in place by the indexing offsets a of the contact blades 85 and the ribs 58 and 59. The contact blades 85 and their manner of mounting to the frame structure 51 are greatly simplified over the prior art. The plug member 80 is ultrasonically welded within the base portion 53 after assembly of the contact blades 85 in order to provide an overall integral frame structure.

In order that the Applicants invention be understood in its broadest application, it should be understood that the frame structure 51 of the drawing may be used almost without need for modification when comprising the main housing body for small electrical devices such as push keys, turn keys and toggle switches. The interior cavity 57 is utilized to contain the plurality of elongated contact blades which are characteristically used with such devices. These contact blades, as are the contact blades 85, can be mounted within a corresponding number of aligned slots provided in the recessed surface area 81 and the plug member 80 of the base portion 53. The tubular open-end front portion 52 of the frame structure 51 readily facilitates the front mounting of actuating buttons and toggle handles in place of the translucent cap structure 65. While the present invention has been shown and described with reference to the preferred embodiment thereof, it is to be understood that the invention is not limited to the precise form set forth herein and that various modifications and changes may be made therein without departing from the spirit and scope of the present invention.

What is claimed is:

1. An improved lamp holder assembly comprising: an elongated frame structure including a front end portion, a base portion and an intermediate cavity defined therebetween for housing an illuminating lamp device therein, said base portion including electrical connecting means for use with said lamp device, said front end portion being open-ended and generally tubular and including a plurality of stepped inner surfaces of different diametrical dimensions each thereof having at least one circumferentially extending slot therein, and a plurality of display cap structures of different diametrical sizes to be insertedly mated with said front end portion through reception within said open-end thereof, each of said cap structures including an enlarged exterior portion to be visibly observed and a reduced portion depending therefrom to be inserted into said open-end, said reduced portion having a ridge area for reception when so inserted within the circumferentially extending slot of a correspondingly diametrically sized inner surface whereby said cap structures are removably secured to said front end portion of said frame structure. i

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 a 777 a 137 Dated December 4 1973 KENT G BLACKMAN JAMES J COSTANZO EUGENE R. HRDLICK Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the Cover Page, [75] add the name KENT G. BLACKMAN Signed and sealed this 15th day of July 1975.

(SEAL) Attest:

- C. MARSHALL DANN RUTH c. MASON Commissioner of Patents Attesting Officer and Trademarks 

1. An improved lamp holder assembly comprising: an elongated frame structure including a front end portion, a base portion and an intermediate cavity defined therebetween for housing an illuminating lamp device therein, said base portion including electrical connecting means for use with said lamp device, said front end portion being open-ended and generally tubular and including a plurality of stepped inner surfaces of different diametrical dimensions each thereof having at least one circumferentially extending slot therein, and a plurality of display cap structures of different diametrical sizes to be insertedly mated with said front end portion through reception within said open-end thereof, each of said cap structures including an enlarged exterior portion to be visibly observed and a reduced portion depending therefrom to be inserted into said open-end, said reduced portion having a ridge area for reception when so inserted within the circumferentially extending slot of a correspondingly diametrically sized inner surface whereby said cap structures are removably secured to said front end portion of said frame structure. 